| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a nonvolatile memory unit having a high voltage endurance between an active region of a substrate and a control gate electrode. <P>SOLUTION: The nonvolatile memory unit has: a substrate having device isolating dielectric trenches; first and second tunnel dielectric films and first and second floating gate electrodes formed on the substrate on both sides of each device isolating trench; an inter-gate dielectric film formed to cover upper surfaces of the first and second floating gate electrodes and to fill at least an upper portion of each device isolating dielectric trench, which is located between the first and second floating gate electrodes and between the first and second tunnel dielectric films; and a control gate electrode formed on the inter-gate dielectric film. The inter-gate dielectric film includes: an electron trap layer made of a first dielectric material having the ability to trap electrons; and first and second dielectric layers made of a second dielectric material smaller than the first material in the ability to trap electrons, and sandwiching the electron trap layer therebetween. <P>COPYRIGHT: (C)2012,JPO&INPIT |
